/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1988 AT&T	*/
/*	  All Rights Reserved  	*/

#pragma weak _des_crypt = des_crypt
#pragma weak _des_encrypt = des_encrypt
#pragma weak _des_setkey = des_setkey

#include <sys/types.h>
#include <crypt.h>
#include "des_soft.h"

#include <stdlib.h>
#include <thread.h>
#include <pthread.h>
#include <sys/types.h>

/*
 * This program implements the
 * Proposed Federal Information Processing
 *  Data Encryption Standard.
 * See Federal Register, March 17, 1975 (40FR12134)
 */

/*
 * Initial permutation,
 */
static char IP[] = {
	58, 50, 42, 34, 26, 18, 10, 2,
	60, 52, 44, 36, 28, 20, 12, 4,
	62, 54, 46, 38, 30, 22, 14, 6,
	64, 56, 48, 40, 32, 24, 16, 8,
	57, 49, 41, 33, 25, 17, 9, 1,
	59, 51, 43, 35, 27, 19, 11, 3,
	61, 53, 45, 37, 29, 21, 13, 5,
	63, 55, 47, 39, 31, 23, 15, 7,
};

/*
 * Final permutation, FP = IP^(-1)
 */
static char FP[] = {
	40, 8, 48, 16, 56, 24, 64, 32,
	39, 7, 47, 15, 55, 23, 63, 31,
	38, 6, 46, 14, 54, 22, 62, 30,
	37, 5, 45, 13, 53, 21, 61, 29,
	36, 4, 44, 12, 52, 20, 60, 28,
	35, 3, 43, 11, 51, 19, 59, 27,
	34, 2, 42, 10, 50, 18, 58, 26,
	33, 1, 41, 9, 49, 17, 57, 25,
};

/*
 * Permuted-choice 1 from the key bits
 * to yield C and D.
 * Note that bits 8, 16... are left out:
 * They are intended for a parity check.
 */
static char PC1_C[] = {
	57, 49, 41, 33, 25, 17, 9,
	1, 58, 50, 42, 34, 26, 18,
	10, 2, 59, 51, 43, 35, 27,
	19, 11, 3, 60, 52, 44, 36,
};

static char PC1_D[] = {
	63, 55, 47, 39, 31, 23, 15,
	7, 62, 54, 46, 38, 30, 22,
	14, 6, 61, 53, 45, 37, 29,
	21, 13, 5, 28, 20, 12, 4,
};

/*
 * Sequence of shifts used for the key schedule.
 */
static char shifts[] = {1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1, };

/*
 * Permuted-choice 2, to pick out the bits from
 * the CD array that generate the key schedule.
 */
static char PC2_C[] = {
	14, 17, 11, 24, 1, 5,
	3, 28, 15, 6, 21, 10,
	23, 19, 12, 4, 26, 8,
	16, 7, 27, 20, 13, 2,
};

static char PC2_D[] = {
	41, 52, 31, 37, 47, 55,
	30, 40, 51, 45, 33, 48,
	44, 49, 39, 56, 34, 53,
	46, 42, 50, 36, 29, 32,
};

/*
 * The C and D arrays used to calculate the key schedule.
 */

static char C[28];
static char D[28];
/*
 * The key schedule.
 * Generated from the key.
 */
static char KS[16][48];

/*
 * The E bit-selection table.
 */
static char E[48];
static char e2[] = {
	32, 1, 2, 3, 4, 5,
	4, 5, 6, 7, 8, 9,
	8, 9, 10, 11, 12, 13,
	12, 13, 14, 15, 16, 17,
	16, 17, 18, 19, 20, 21,
	20, 21, 22, 23, 24, 25,
	24, 25, 26, 27, 28, 29,
	28, 29, 30, 31, 32, 1,
};

/*
 * Set up the key schedule from the key.
 */

static mutex_t lock = DEFAULTMUTEX;

static void
des_setkey_nolock(const char *key)
{
	int i, j, k;
	char t;

	/*
	 * First, generate C and D by permuting
	 * the key.  The low order bit of each
	 * 8-bit char is not used, so C and D are only 28
	 * bits apiece.
	 */
	for (i = 0; i < 28; i++) {
		C[i] = key[PC1_C[i]-1];
		D[i] = key[PC1_D[i]-1];
	}
	/*
	 * To generate Ki, rotate C and D according
	 * to schedule and pick up a permutation
	 * using PC2.
	 */
	for (i = 0; i < 16; i++) {
		/*
		 * rotate.
		 */
		for (k = 0; k < shifts[i]; k++) {
			t = C[0];
			for (j = 0; j < 28-1; j++)
				C[j] = C[j+1];
			C[27] = (char)t;
			t = D[0];
			for (j = 0; j < 28-1; j++)
				D[j] = D[j+1];
			D[27] = (char)t;
		}
		/*
		 * get Ki. Note C and D are concatenated.
		 */
		for (j = 0; j < 24; j++) {
			KS[i][j] = C[PC2_C[j]-1];
			KS[i][j+24] = D[PC2_D[j]-28-1];
		}
	}

	for (i = 0; i < 48; i++)
		E[i] = e2[i];
}

void
des_setkey(const char *key)
{
	(void) mutex_lock(&lock);
	des_setkey_nolock(key);
	(void) mutex_unlock(&lock);
}

/*
 * The 8 selection functions.
 * For some reason, they give a 0-origin
 * index, unlike everything else.
 */
static char S[8][64] = {
	14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,
	0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,
	4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,
	15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13,

	15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,
	3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,
	0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,
	13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9,

	10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,
	13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,
	13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,
	1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12,

	7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,
	13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,
	10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,
	3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14,

	2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,
	14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,
	4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,
	11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3,

	12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,
	10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,
	9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,
	4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13,

	4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,
	13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,
	1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,
	6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12,

	13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,
	1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,
	7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,
	2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11,
};

/*
 * P is a permutation on the selected combination
 * of the current L and key.
 */
static char P[] = {
	16, 7, 20, 21,
	29, 12, 28, 17,
	1, 15, 23, 26,
	5, 18, 31, 10,
	2, 8, 24, 14,
	32, 27, 3, 9,
	19, 13, 30, 6,
	22, 11, 4, 25,
};

/*
 * The current block, divided into 2 halves.
 */
static char L[64];
static char tempL[32];
static char f[32];

/*
 * The combination of the key and the input, before selection.
 */
static char preS[48];

/*
 * The payoff: encrypt a block.
 */

static void
des_encrypt_nolock(char *block, int edflag)
{
	if (edflag)
		(void) _des_decrypt1(block, L, IP, &L[32],
		    preS, E, KS, S, f, tempL, P, FP);
	else
		(void) des_encrypt1(block, L, IP, &L[32],
		    preS, E, KS, S, f, tempL, P, FP);
}

void
des_encrypt(char *block, int edflag)
{
	(void) mutex_lock(&lock);
	des_encrypt_nolock(block, edflag);
	(void) mutex_unlock(&lock);
}



#define	IOBUF_SIZE	16

static char *
_get_iobuf(thread_key_t *keyp, unsigned size)
{
	char *iobuf;

	if (thr_keycreate_once(keyp, free) != 0)
		return (NULL);
	iobuf = pthread_getspecific(*keyp);
	if (iobuf == NULL) {
		if (thr_setspecific(*keyp, (iobuf = malloc(size))) != 0) {
			if (iobuf)
				(void) free(iobuf);
			iobuf = NULL;
		}
	}
	return (iobuf);
}

char *
des_crypt(const char *pw, const char *salt)
{
	int	i, j;
	char	c, temp;
	char block[66];
	static thread_key_t key = THR_ONCE_KEY;
	char *iobuf = _get_iobuf(&key, IOBUF_SIZE);

	(void) mutex_lock(&lock);
	for (i = 0; i < 66; i++)
		block[i] = 0;
	for (i = 0; (c = *pw) && (i < 64); pw++) {
		for (j = 0; j < 7; j++, i++)
			block[i] = (c>>(6-j)) & 01;
		i++;
	}

	des_setkey_nolock(block);

	for (i = 0; i < 66; i++)
		block[i] = 0;

	for (i = 0; i < 2; i++) {
		c = *salt++;
		iobuf[i] = (char)c;
		if (c > 'Z')
			c -= 6;
		if (c > '9')
			c -= 7;
		c -= '.';
		for (j = 0; j < 6; j++) {
			if ((c>>j) & 01) {
				temp = E[6*i+j];
				E[6*i+j] = E[6*i+j+24];
				E[6*i+j+24] = (char)temp;
			}
		}
	}

	for (i = 0; i < 25; i++)
		(void) des_encrypt_nolock(block, 0);

	for (i = 0; i < 11; i++) {
		c = 0;
		for (j = 0; j < 6; j++) {
			c <<= 1;
			c |= block[6*i+j];
		}
		c += '.';
		if (c > '9')
			c += 7;
		if (c > 'Z')
			c += 6;
		iobuf[i+2] = (char)c;
	}
	iobuf[i+2] = 0;
	if (iobuf[1] == 0)
		iobuf[1] = iobuf[0];
	(void) mutex_unlock(&lock);
	return (iobuf);
}
